Telephone lines, which are carried by electrical conductors known as tip ring wire pairs, are generally aggregated at a particular point in a building prior to being distributed and connected to various types of telephone equipment, such as, for example, telephones, fax machines, modems etc. As the tip ring pairs generally enter the building as part of a multi-conductor cable, the individual tip ring wire pairs must first be broken out from the cable into individual wire pairs. This is normally accomplished in a junction box known as, for example, a building entrance protector (BEP), or network interface unit (NIU). Within such devices the individual telephone line tip ring pairs are separated from the cable, individually connected to a connector block, and made available for further electrical connection and distribution. Usually there is a protector device inserted between the telephone and central office, or network side of the telephone line and the customer equipment or terminal side of the telephone line to protect the telephone and user, or other equipment connected to the telephone line, from hazardous overvoltages induced in the telephone network or in the cables passing between the telephone central office and the building within which the line is terminated.
In a typical arrangement, the telephone lines coming from the network are first wired to a protector field, which is an array of connectors for receiving the protector device, which is in turn hard wired to a first connector block which provides a first test point for testing the telephone line connections between the building and telephone central office. This first terminal block is hard wired to a multi pair connector, most typically a twenty-five pair connector of the RJ21 type, for further connection to an array of customer bridges which are also hard wired and connectorized via a mating RJ21 connector. The use of a customer bridge permits a subscriber to disconnect terminal equipment from a telephone line so that the subscriber can isolate troubles on the line as originating in the telephone network, or on the terminal equipment side of the telephone line.
Additionally, there are known insulation displacement connector (IDC) blocks for use in such junction boxes and/or distribution fields, such as the ubiquitous punch down connector block, also known as a 66-type connector block, and the tool-less insulation displacement connector blocks utilizing push cap connectors, such as that described in U.S. Pat. No. 4,913,659 dated Apr. 3, 1990, the entire disclosure of which is incorporated herein by reference. Such a connector block is commercially available under the product designation SC99 from Lucent Technologies Inc. Other connectors used for telephony wiring applications are described in U.S. Pat. No. 4,662,699 to Vachhani et al., dated May 5, 1987, and in U.S. Pat. No. 3,611,264 to Ellis, dated Oct. 5, 1971. Also widely available are tool-less IDC's known as Mini-Rocker Connectors such as those sold by A. C. Egerton Ltd., which hold a tip-ring wire pair in terminals retained under a single movable cap through which both wires of the pair are inserted.
The cap section and base section of mini-rocker tool-less IDC connectors are held together by a latching mechanism known in the art. This prior art latching mechanism does not include any means to retain the latch in an engaged position. In order to achieve good latching performance, a significant amount of movement and deflection of the latch is required. This movement is facilitated by a living hinge. Reference is first made to FIG. 1 which illustrates an insulation displacement connector constructed in accordance with the prior art, generally indicated as 10. Connector 10 has a cap section, generally indicated as 12, and a base section, generally indicated as 14. Cap section 12 is hingedly connected to base section 14 at a hinged pivot point 32. Cap section 12 pivots about pivot point 32 and is movable between an open position and a closed position. FIG. 1 illustrates cap section 12 in the closed position. Base section 14 is fixed and generally includes at least one terminal strip 28 of an art recognized type.
Cap section 12 includes a latch 15 which is movable between an engaged position and a disengaged position. FIG. 1 illustrates latch 15 in the engaged position. Latch 15 includes a latch engaging portion 16. Base section 14 includes a latch retaining portion 38. When cap section 12 is in the closed position, as illustrated in FIG. 1, latch 15 is in the engaged position. In this orientation, latch engaging portion 16 confrontingly abuts and engages latch retaining portion 38, thereby maintaining cap section 12 in the closed position. In order to open cap section 12, latch 15 must first be moved to the disengaged position. Latch 15 is maintained in its engaged position by the elasticity of a living hinge 24.
Latch 15 also includes a latch base 17 which is used in conjunction with a finger grip member 34. Latch base 17 and finger grip member 34 have defined therebetween an aperture 36. Movement of latch 15 between the engaged and disengaged positions can be accomplished by gripping connector 10 between latch 15 and finger grip member 34. Upon the application of pressure, latch 15 pivots about living hinge 24, with engaging portion 16 moving in direction Z while latch base 17 is pressed in direction Y. By applying sufficient pressure such that latch 15 is pivoted about living hinge 24 by a sufficient distance in the Z direction, latch engaging portion 16 can be disengaged from latch retaining portion 38, and cap section 12 can be moved into the open position.
While this prior art IDC works for its intended purpose, a significant drawback to this prior art IDC is that with the passage of time and the effects of changes in temperature and pressure, living hinge 24 tends to lose its elastic properties. Consequently, latch 15 can become disengaged from its engaged position because latching engaging portion 16 can slide out and away from latch retaining portion 38. Thus, if the connector wires are pulled upward during a wire tracing operation, as known in the art, the cap tends to open. This can cause early and unwanted disengagement of the wires from the connector, permitting installed wires to disconnect.